What is the meaning of "majoritarianism" as a principle of democratic group decision-making in a judgement aggregation problem, when the propositionwise majority view is logically inconsistent? We argue that the majoritarian ideal is best embodied by the principle of "supermajority efficiency"...

We show that, in a sufficiently large population satisfying certain statistical regularities, it is often possible to accurately estimate the utilitarian social welfare function, even if we only have very noisy data about individual utility functions and interpersonal utility comparisons. In...

A ``difference preorder'' is a (possibly incomplete) preorder on a space of state changes (rather than the states themselves); it encodes information about preference intensity, in addition to ordinal preferences. We find necessary and sufficient conditions for a difference preorder to be...

We introduce a two-stage ranking of multidimensional alternatives, including uncertain prospects as particular case, when these objects can be given a suitable matrix form. The first stage defines a ranking of rows and a ranking of columns, and the second stage ranks matrices by applying natural...

Some social choice models assume that precise interpersonal comparisons of utility (either ordinal or cardinal) are possible, allowing a rich theory of distributive justice. Other models assume that absolutely no interpersonal comparisons are possible, or even meaningful; hence all...

Academic research is a public good whose production is supported by the tuition-paying students that a faculty's research accomplishments attract. A professor's spot contribution to the university's revenues thus depends not on her spot research production, but rather on her cumulative research...

Let S be a set of logically related propositions, and suppose a jury must decide the truth/falsehood of each member of S. A `judgement aggregation rule' (JAR) is a rule for combining the truth valuations on S from each juror into a collective truth valuation on S. Recent work has shown that...

Given a bargaining problem, the `relative utilitarian' (RU) solution maximizes the sum total of the bargainer's utilities, after having first renormalized each utility function to range from zero to one. We show that RU is `optimal' in two very different senses. First, RU is the maximal element...

Given a set of propositions with unknown truth values, a `judgement aggregation rule' is a way to aggregate the personal truth-valuations of a set of jurors into some `collective' truth valuation. We introduce the class of `quasimajoritarian' judgement aggregation rules, which includes majority...

We define an intergenerational social welfare function Sigma from |R^|N (the set of all infinite-horizon utility streams) into *|R (the ordered field of hyperreal numbers). The function Sigma is continuous, linear, and increasing, and is well-defined even on unbounded (e.g. exponentially...